if more than 64 distinct values had been used.

for each object. For value code, pointer to the actual value data
is used. The actual problem arises from the fact that 'actual' e.g.
runtime data is stored in array and that array is auto-growing. There is
special hook (update_tvalue() function) which is used to update the pointers
after the change. For some reason, object 'key' was not updated.
Fix this by adding update code to the update_tvalue().